Adjustable cutter for strip mining machines



Jan. 19, 1954 J. c. SPROUL ADJUSTABLE CUTTER FOR STRIP MINING MACHINES Filed Feb. 25, 1950 3 Sheets-Sheet l QWW ON mmm mm mm Inventor:

M Attorneys Jan. 19, 1954 J. c. SPROUL 2,666,629

ADJUSTABLE CUTTER FOR STRIP MINING MACHINES Filed Feb. 25, 1950 5 Sheets-Sheet 2 Attorne ys 195.4 J. c. SPROUL v ADJUSTABLE CUTTER FOR STRIP MINING MACHINES 3 Sheets-Sheet 3 Filed Feb. 25, 1950 zec' Inventor: t/Z /M a/r/m 67 90:

Attorneys V Patented Jan. 19, 1954 oFFIcE-i] ADJUSTABLE CUTTER FOR STRIP MINING MACHINES John Connel Sproul, Glasgow, Scotland, assignor to Mavor & Coulson, Limited Application February 25, 1950, Serial No. 146,182

. 2 Claims. 1 p

This invention relates to mining machines belonging to a previously proposed type having a cutter head adapted to strip off coal or other mineral in the advance of the machine by wedging or splitting the mineral wedge-wise along a plane approximately parallel to the face of the seam. Where, as is usually desirable, the machine is double-ended-that is to say, is designed to work in each of its two directions of travelthere are two such cutter heads.

The cutter head may incorporate two or more superposed chisel-like cutters arranged to strip off the mineral at different levels, these cutters having edges which are co-planar, or approxi mately so, in order that the cutters act along a plane behind and roughly parallel to the fac of the seam.

It is desirable that the cutter or cutters shall be laterally adjustable in order that the chisellike action canbe regulated to suit conditions imposed by any particular coal seam or by the operations of the machine.

It has been ascertained that, for a lateral adjustment to be fully effective, it is desirable that the lateral motion of a cutter shall be accompanied by a corresponding angular correction. That is to say, if a cutter is advanced laterally to cut deeper, it is desirable that the angle .of the cutter to the face of the seam shall be greater; conversely, if the cutter is withdrawn laterally, its angle to the face should be correspondingly decreased.

The object of the present invention is to provide improved means by virtue of which the operator will be enabled to adjust the lateral and angular setting of the cutter or cutters conveniently, positively and accurately.

According to the invention, in a mining. machine of the type stated, a cutter is pivotally mounted on a support and is connected thereto so as to be adjustable both angularly and laterally about the pivot by a toggle link under the control of a screw.

The screw may be journalled on the support and threaded through a nut slidable on the support and connected by the toggle link to the cutter.

A machine of the before-mentioned type, designed for mining coal, is shown by way of example in the accompanying drawings to illustrate the invention. In the drawings, Figs. 1 and 2 are a diagrammatic side elevation and a plan of the machine. Fig. 3 is a side elevation of the cutter head, drawn to a larger scale, the view being partly in section approximately on the line I (Cl. 262-8) 2 3-3 of Fig. 4. Fig. 4 is a corresponding plan of the cutter head, thisview being partly in section on the line 4 of Fig. 3. Fig. 5 is a fragmentary section drawn to a still larger scale approxi- I vmately on the line 55 of Fig. 4. Fig. 6 is a sectional elevation corresponding to Fig. 5, thesection being on the line 66 of Fig. 1.

The general arrangement of the mining machine to which the invention is shown applied-is drawn in simple outline in Figs. 1 and 2, the construction and operation of the machine in gen-' eral not being material to the present invention; In order that the relationship of the invention to the machine can be adequately understood, the following brief description of the machine is given.

The machine shown is double-ended, comprising mainly a framelike body 1, 8, 9 and ID, a carriage i I and two cutter heads I2 and I3. The body consists of two transverse end walls 7 and 8,- to which the headsare connected, and two longitudinal guide bars 9 and ID, on which the carriage is slidably mounted.

The carriage incorporates hydraulic propulsion apparatus. This apparatus includes a vertical hydraulic jack consisting of a cylinder ldwith a foot 45, "the cylinder being vertically movable i'l'lz--' a holder l6 incorporated in the carriage, and a piston-operated head .I'! which normally rests upon the holder. The propulsion apparatus also includes a hydraulic ram unit consisting of a horizontal cylinder 18 and a ram l9 extending from both ends of the cylinder and engageable' at its ends with the walls 1 and 8.

In order that the machine shall be propelled say from left to right (as viewed in Figs. land 2) the jack is operated firstly to depress its foot [5 against the floor of the mine and secondly'to lift its head I! against the mine roof- The jack. thus extended provides a securely anchored abutment. that the ram [9 is forced to the right, the ram thus engaging the wall 8 and pushing the framelike body lli, with the head I3 leading, upon the mine floor towards the right, the guide bars 9, it sliding through the now stationary carriage l I. Thus, the head 13 performs its cutting stroke.

Thereafter, the jack is operated so that its head is lowered and its foot raised, thus contracting, the jack and freeing it from the roof and floor.. Finally, the ram unit is operated so that the ram I9 is forced to. the left, the ram thus engaging the rear wall 7 and pushing the carriage ilso that it freely slides to the right hand end of the guide bars 9, Hi to take up a new position of an- Next the ram unit is operated so :1

3 chorage for the next cutting stroke.- This completes the cycle of operations.

Both cutter heads I2 and [3 are of similar construction. Therefore only one of the heads, namely the right hand head !3, is hereinafter described.

In the example, the cutter head comprises a leading cutter 29 at an intermediatelevel two cutters 21' and 22 above the cutter 20, a floor cutter 23 and a roof cutter 24. The cutters -24 have edges 20A-24A all nearly in the same vertical plane .A, Figs. 2 and: 4'. 'I'he:.floor.

and roof cutters also have horizontal edges'23B 24B. The floor cutter is associated with a sloping ramp 23C for lifting the coal from the floor and deflecting it sidewise from the path of" the machine for conveyance from:themine workings-r Referring also to Figs. 3 to 6, each of the main cutters 20, 2|, 22 and 23 is an edged plate that is attached to an approximately wedge-like body,

the bodies being indicated by 25', 26, 21 and 28 respectively. It'will' be noted" that the body 25 of the: intermediate. cutter 23 is considerably longer than the bodies 23; 2'! and 28, so that the" of a lever with a central bearing boss, the several. bosses being indicated by 25A,,25A, 21A and 28Arespectively. From each boss there extends an arm 25B, 26B, 213 or 28B of the lever concerned; Each of these arms is in the form of' an interconnected pair of upper and lower cheeks, and: all of these cheeks have terminal eyepieces 25C28C, which bear against'verticalthrust plugs:4'l fitted into the shelves 29A-29C. Theseplugs 4|, as Figs. 3'and 5 show, eachconsist of a cylindrical body, which fits firmly into aholev in the shelf above or below the plug and of. a flange which serves as a slide bearing surfacez for the associated cutter-lever boss 25C,v 21C or 28C. The fulcrum of the'four. lever- 2 66, like. bodies the parts'of which 25-28 is a four-part pivot pin 3|, fit slidably through the bosses 25Auto 28A and also through co-axial bearings 32 in the casing. shelves 29'A--29'C.' The lowermostip'art of. the pin 3| is supported by a crosspin3lA.

The" cutter: bodies are made like-levers in order thattthey canzbe pivotally adjusted so as to vary. not. only the lateral setting, the cutting depth of a cutter, but also-the angulan setting of the. cutters 2024 individually inzrelationto the supporting casing 29. Therefore. each cutter body. has adjustment means forfiadjusting it laterally and angularly. In the example,themeans provided for each body'com prises the following components:

A turnablescrew 33 whichv is journalled'in a bracket33A on one of four coversbolted-to the casing. 29 and form aclosure to the: front side of the compartments thereof;

A nut 35 which is slidable along a horizontal inner slideway 36 in the associated cover and through which ordinarily the screw 33 is threaded;

A link:31 pivotally connected atits opposite ends by a pin 38 to the associated nut 35 and The casing 29 is attached by a conwhich determines 34 that are at by a pin 39 to the eye-piece of the associated lever arm 25B, 26B, 21B or 283.

In order to adjust any of the cutters laterally and angularly, the associated screw 33 is turned appropriately, say by means of a ratchet-lever, or a spanner, engageable with a square head 40 on the screw, this head extending from the casing 29. Suchturning of the screw causes the nut 35 to move along its slideway 3'5 and the link 31 to move angularly in the manner of a toggle-link, so that the cutter is forced with the power: thatis: a characteristic of toggle action to change its angular relationship to the casing 29. It will be apparent that the force transmitted? tothe cutter is in the nature of a powerfur thrust or pull through the link 31. The reactionst'othis thrust or pull is derived mainly from the slideway 36, the stress taken by the screw -and-nut pair 33, 35 being purely axial. Thus, distortion and wear and slack are reduced to the minimum;

In order to interchange any two of the cutter bodies 25, 26 and 21, the pivot pin 3i is withdrawn upwards part-by-part so far as necessary. The appropriate two screws 33 are unscrewed from their nuts 35' and these nuts are slid from their slideways 36'. The two associated covers 34 are unbolted and removed, together with their screws 33'. Thus, in each of the two compartments whose covers have been removed, the following components' lie exposed;,namely the nut 33, its link 31 and the cutter-lever'arm 25Bor 2613 or 2B or 28B,.as the case may be, all of said components being freely withdrawable as an assembly from their compartments. Accordingly, each of thetwo cutter bodies to be inter changed and the associated assembly of components 35, 31, 38 and 39 are removed from the cutter head. During removal, the pins 39 concerned each slide freely between and away from the vertical-thrust plugs 41 fitted in the shelves above and below, eachof said pins remaining as the pivotal connection between its link 31 and cutter-lever arm.

Patent application No. 146,181 of the same date as the present application shows and describes a mining. machine the same as is shown and described in the present application but claims an inventionv that is different from the invention hereinafter claimed.

I claim:

1. A mining machine of the type stated having a cutter head, a casing incorporated in the cutter head,,a detachable'co'ver on said casing, a lever whicn'is fulcrumed inside said casing so as to be angularly movable in relation thereto, a cutter carried by said lever so as to'project both later ally andv angularly forwards outside said casing, aturnable cutter-adjusting screw journalled on" said cover to have astationary location inside said'casing; a nut through which said screw is threadedthe nut being movable along the screw, a link pivotally connected to' said nut and to" said lever in the manner of a toggle so as to force the. lever powerfully into a setting. giving a required extent of projection and degree of angularity to the cutter in relation to the casing Whenever the screw is rotated, and a guideway provided on the inner side of said cover, said guide'way being stationarily located inside said casing and said nut being slidable along the guideway on rotation of said screw so. that said guideway provides the reaction to the powerful thrust and pull of said link and confines said nut and screw to purely axial stress despite the angular movements of said lever and link.

2. A mining machine of the type stated having a cutter head formed with a compartment, a

detachable cover on said head closing said compartment, a lever which is fulcrumedo'n said head so as to be angularly movable thereon, a cutter carried by said lever so as to project forwards and laterally from said head, a cutter-adjusting screw turnably mounted on said cover in a stationary location, a nut through which ,said screw,

is threaded, the nut being movable along the screw, a link pivotally connected to said nut.

and to said lever in the manner of a toggle so as to iorce the lever powerfully into a setting giving a required extent of projection and degree of angularity to the cutter in relation to the head whenever the screw is rotated, and a guideway stationarily located on said cover along which guideway said nut is slidable on rotation of said screw, said screw, nut, link and a portion of the l t eferences Cited in thefile ofthis patent UNITED STATES PATENTS Number Name Date 1,637,531 Morgan Aug. 2, 1927 1,675,494 Jennings et a1. July 3, 1928 1,710,801 Morgan Apr. 30, 1929 1,711,280; Morgan Apr. 30, 1929 2,389,920 Mavor Nov. 27, 1945- 2,580,569

Mavor Jan. 1, 1952 

